Tube flow limiter, safety flow clip, and tube pincher mechanism

• US 5,437,635 A
• Filed: 12/14/1993
• Issued: 08/01/1995
• Est. Priority Date: 05/06/1992
• Status: Expired due to Term

• Current Assignee: B Braun Medical Incorporated (B. Braun Holding GmbH & Co. KG)
• Original Assignee: McGaw, Inc. (B. Braun Holding GmbH & Co. KG)
• Inventors: Fields, Antony, Rasmussen, Edward G., Branson, Terry, Harrison, David J., Raines, Aaron T., Owens, Dana J.
• Primary Examiner(s): Rosenbaum, C. Fred
• Assistant Examiner(s): WILKENS, FRANK
• Application Number:
  US08/167,413
• Time in Patent Office: 595 Days
• Field of Search: 604/4-6, 604/34, 604/65-67, 604/151, 604/153, 604/245, 604/246, 604/250, 128/DIG. 12, 128/DIG. 13, 251/7, 251/9
• US Class Current: 604/65
• CPC Class Codes: A61M 2205/14 Detection of the presence or absence of a tube, a connector or a container in an apparatus
• CPC Class Codes: A61M 39/281 Automatic tube cut-off devices, e.g. squeezing tube on detection of air
• CPC Class Codes: A61M 39/287 Wedge formed by a slot having varying width, e.g. slide clamps
• CPC Class Codes: A61M 5/16813 by controlling the degree of opening of the flow line
• CPC Class Codes: A61M 5/365 Air detectors A61M5/1684 takes precedence; in extracorporeal blood circuits A61M1/3626
• CPC Class Codes: Y10S 128/12 Pressure infusion

Abstract

A flow limiter mechanism for use with an infusion pump of the type operating upon a disposable cassette held by the infusion pump and having a flow tube connected to the cassette. The flow limiter includes a receiving channel located on the infusion pump adjacent to the disposable cassette held by the infusion pump. A tube pincher is operatively associated with the receiving channel to pinch the flow tube in a clamped position and mechanically retractable to an unclamped position to allow the flow tube to open. Electrical controls are connected for selectably operating the tube pincher from the clamped closed position to the unclamped opened position while the disposable cassette is held by the infusion pump. A flow clip is attached to the flow tube and is manually operable between opened and closed clipping positions prior to inserting the disposable cassette into the infusion pump. The flow tube and attached flow clip are prevented from being removed from the flow limiter mechanism unless the flow clip is in the closed clipping position.

Claims

1. A flow limiter mechanism in an infusion pump of the type having a channel for receiving a flow tube connected to a disable pumping cassette, said flow limiter mechanism comprising:

a) a tube pincher operatively associated with said receiving channel, said tube pincher having a clamped position to stop flow in said flow tube received in said receiving channel, and said tube pincher having an unclamped position to allow flow in said flow tube, and which tube pincher is mechanically retractable to an unclamped position;

b) electrical controls for selectably operating said tube pincher from said clamped position to said unclamped position while said flow tube connected to said disposable cassette is received in said receiving channel of said infusion pump;

c) a flow clip attached to said flow tube manually operable between opened and closed clipping positions prior to receiving said flow tube into said receiving channel; and

d) means cooperatively associated between said flow clip and said receiving channel for preventing removal of said flow tube from said receiving channel when said flow clip is in said opened position and for permitting removal of said flow tube from said receiving channel when said flow clip is in said closed clipping position.

2. A flow limiter mechanism as in claim 1 wherein said tube pincher further comprises:

a) a slot perpendicular to and partially through said receiving channel;

b) a pincher lever arm pivotally mounted to said flow limiter mechanism aligned with said perpendicular slot and positioned for selectable pivoting into and out of said receiving channel;

c) an anvil surface positioned adjacent said perpendicular slot for supporting said flow tube in said receiving channel against said pincher lever arm so that it is compressed therebetween when said pincher lever arm pivots through said perpendicular slot into said receiving channel against said flow tube received in said receiving channel;

d) a spring, biased for pivoting said pincher lever arm at least partially through said perpendicular slot into said receiving channel so that receiving said flow tube into said receiving channel is blocked thereby; and

e) a manual actuation device connected to said pincher lever arm for mechanically pivoting the arm against said spring bias out of said receiving channel to allow receiving said flow tube thereinto.

3. A flow limiter mechanism as in claim 2 wherein the electrical controls for selectably operating said tube pincher from said clamped position to said unclamped position further comprises:

a) a lifting lever pivotably mounted to said flow limiter mechanism and having an end for contacting said pincher lever arm; and

b) a solenoid connected to said lifting lever arm for pivoting said end thereof to contact said pincher lever arm and to thereby lift said pincher lever arm to said open position.

4. A flow limiter mechanism as in claim 1 wherein said means cooperatively associated with said flow clip and said receiving channel for preventing removal of said flow tube from said receiving channel further comprises:

a) a clip carrier attached to said flow tube of said disposable cassette and slidably holding said flow clip perpendicular to said flow tube;

b) a carrier receptacle mounted adjacent said receiving channel for receiving said clip carrier, said flow clip held by said clip carrier and by said flow tube to which said flow clip is attached, all in a predetermined alignment; and

c) gripping arms pivotally mounted in said carrier receptacle aligned with said flow clip for gripping said clip carrier upon receiving said clip carrier when said flow clip is in said opened clipping position and for releasing said clip carrier when said flow clip is in said closed clipping position.

5. A flow limiter mechanism as in claim 1 wherein said flow clip which is manually operable between said opened and closed clipping positions, further comprises a clip body defining an orifice sized for passing said flow tube therethrough, and defining a slit interconnected with said orifice, said slit having walls spaced apart a sufficiently wide distance to allow said flow tube to be manually slid into said slit with application of conveniently low force and said walls spaced apart a sufficiently close distance to clip said flow tube closed when said flow tube is slid into said slit.

6. A flow limiter mechanism as in claim 4 further comprising:

a) a central processor interconnected to said electrical controls of said tube pincher;

b) a door operatively associated with said flow limiter mechanism having a first closed position for holding said disposable pumping cassette with said flow tube in said receiving channel and a second open position for releasing said disposable pumping cassette;

c) a door sensor interconnected with said door for providing a signal to said central processor indicating whether said door is in a first closed or a second opened position;

d) a carrier sensor interconnected to provide a signal to said central processor indicating whether said flow clip carrier is properly installed in said receiving channel; and

e) a central processor program for enabling said electrical controls of said tube pincher to be activated between said first closed and said second opened position upon receiving signals both from said door sensor indicating that it is in said first closed position and also from said carrier sensor indicating that a clip carrier is properly installed.

7. A flow limiter mechanism as in claim 1 further comprising:

a) a tube pincher lever pivotably mounted to said flow limiter mechanism having an engaged and a disengaged pivot position and having a portion thereof for engaging against said flow tube of said disposable cassette with sufficient force to pinch said flow tube closed in said engaged position and a second portion thereof for mechanically pivoting said tube pincher lever between said engaged and disengaged positions; and

b) a loading button mounted on said flow limiter mechanism and operable with a conveniently low manual force for contacting said second portion of said tube pincher lever arm to pivot said engaging portion out of said engaged position.

14. A flow limiter mechanism as in claim 1 further comprising:

a) a tube pincher lever pivotably mounted to said infusion pump having an engaged and a disengaged pivot position and having a portion thereof for engaging against a flow tube of a disposable cassette with sufficient force to pinch said flow tube closed in said engaged position and a second portion thereof for mechanically pivoting said tube pincher lever between said engaged and disengaged positions; and

b) a loading button mounted on said infusion pump and operable with a conveniently low manual force for contacting said second portion of said tube pincher lever arm to pivot said engaging portion out of said engaged position.

8. A flow limiter mechanism for limiting flow in a disposable pumping cassette of the type having flow tubing connected to and extending from said pumping cassette, said flow limiter mechanism comprising:

a) a channel into which channel said flow tubing is received;

b) a tube pincher operatively associated with said receiving channel having a first position in which said received flow tubing is mechanically pinched to stop flow therein and having a second position at which said tube pincher is retracted from said received flow tubing to allow flow therein;

c) mechanical means for retracting said tube pincher from said clamped position;

d) electrical controls for ;

selectably operating said tube pincher from said first position to said second position while said flow tubing is received in said receiving channel;

e) a flow clip, attached to said flow tubing, separately from said tube pincher, having an opened clipping position and a closed clipping position, said flow clip manually movable between said opened clipping position and said closed clipping position before said flow tubing is received into said receiving channel; and

f) clip receiving means for receiving said flow clip attached to said flow tubing, said clip receiving means cooperatively associated with said flow clip and with said receiving channel for preventing removal of said flow clip and said attached flow tubing therefrom, unless said flow clip is in said closed clipping position.

9. A flow limiter mechanism as in claim 8 wherein said tube pincher further comprises:

a) a slot perpendicular to and partially through said receiving channel;

b) a pincher lever arm pivotally mounted to said flow limiter mechanism aligned with said perpendicular slot and positioned for selectable pivoting into and out of said receiving channel;

c) an anvil surface positioned adjacent said perpendicular slot for supporting said flow tubing in said receiving channel against said pincher lever arm so that it is compressed therebetween when said pincher lever arm pivots through said perpendicular slot into said receiving channel against an inserted flow tube;

d) a bias means for pivoting said pincher lever arm at least partially through said perpendicular slot into said receiving channel so that receiving of said flow tubing into said receiving channel is blocked thereby; and

e) wherein said mechanical means for retracting includes a manual actuation device connected to said pincher lever arm for pivoting said lever arm against said bias means out of said receiving channel, thereby allowing said flow tubing to be received thereinto.

10. A flow limiter mechanism as in claim 8 wherein said electrical controls for selectably operating said tube pincher between said clamped and said unclamped positions further comprises:

a) a lifting lever pivotably mounted to said flow limiter mechanism and having an end for contacting said pincher lever arm; and

b) an electrical a solenoid connected to said lifting lever arm for pivoting said end of said lifting level to contact said pincher lever arm and to thereby lift said pincher lever arm to said open position.

11. A flow limiter mechanism as in claim 8 wherein said means cooperatively associated with said flow clip and with said receiving channel for preventing removal of said flow tubing from said receiving channel further comprises:

a) a clip carrier attached to said flow tubing of said disposable cassette and slidably holding said flow clip perpendicular to said flow tubing;

b) a carrier receptacle mounted adjacent to said receiving channel for receiving said clip carrier, said flow clip held by said clip carrier, and said flow tubing to which said flow clip is attached, all received in a predetermined alignment; and

c) gripping arms pivotally mounted in said carrier receptacle aligned with said flow clip for gripping said clip carrier upon receiving said clip carrier when said flow clip is in its opened clipping position and for releasing said clip carrier when said flow clip is in said closed clipping position.

12. A flow limiter mechanism as in claim 8 wherein said flow clip which is manually operable between said opened and closed clipping positions, further comprises a clip body defining an orifice sized for passing a flow tubing therethrough, and defining a slit interconnected with said orifice, said slit having walls spaced apart a sufficiently wide distance to allow said flow tubing to be manually slid into said slit with application of conveniently low force and said walls spaced apart a sufficiently close distance to clip said flow tube dosed when said flow tube is slid into said slit.

13. A flow limiter mechanism as in claim 11 further comprising:

a) a central processor interconnected to said electrical controls of said tube pincher;

b) a door operatively associated with said flow limiter mechanism having a first closed position for holding said cassette with said flow tube in said receiving channel and a second open position for releasing said cassette;

c) a door sensor interconnected with said door for providing a signal to said central processor indicating whether said door is in a first closed or a second opened position;

d) a carrier sensor interconnected to provide a signal to said central processor indicating whether said flow clip carrier is properly installed in said receiving channel; and

e) a central processor program for enabling said electrical controls of said tube pincher to be activated between said first closed and said second opened position upon receiving signals both from said door sensor indicating that it is in said first closed position and also from said carrier sensor indicating that a clip carrier is properly installed.